import sys
input=sys.stdin.readline
def main():
	R,C,K=map(int,input().split())
	lis=[[0]*(C) for i in range(R)]
	for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	dp0=[[0]*(C+1) for i in range(R+1)]
	dp1=[[0]*(C+1) for i in range(R+1)]
	dp2=[[0]*(C+1) for i in range(R+1)]
	dp3=[[0]*(C+1) for i in range(R+1)]
	for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1]))
if __name__ == '__main__':
	main() import sys sys input=sys.stdin.readline input sys.stdin.readline sys.stdin sys stdin readline def main():
	R,C,K=map(int,input().split())
	lis=[[0]*(C) for i in range(R)]
	for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	dp0=[[0]*(C+1) for i in range(R+1)]
	dp1=[[0]*(C+1) for i in range(R+1)]
	dp2=[[0]*(C+1) for i in range(R+1)]
	dp3=[[0]*(C+1) for i in range(R+1)]
	for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1])) main R,C,K=map(int,input().split()) R map(int,input().split()) map int input().split() ().split () input split C K [0]*(C) for i in range(R) for i in range(R) i range(R) range R for i in range(R) [0]*(C) [0] 0 C lis=[[0]*(C) for i in range(R)] lis [[0]*(C) for i in range(R)] for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	 i range(K) range K a,b,c=map(int,input().split()) a map(int,input().split()) map int input().split() ().split () input split b c lis[a-1][b-1]=c lis[a-1][b-1] [a-1] lis a-1 a 1 b-1 b 1 c [0]*(C+1) for i in range(R+1) for i in range(R+1) i range(R+1) range R+1 R 1 for i in range(R+1) [0]*(C+1) [0] 0 C+1 C 1 dp0=[[0]*(C+1) for i in range(R+1)] dp0 [[0]*(C+1) for i in range(R+1)] [0]*(C+1) for i in range(R+1) for i in range(R+1) i range(R+1) range R+1 R 1 for i in range(R+1) [0]*(C+1) [0] 0 C+1 C 1 dp1=[[0]*(C+1) for i in range(R+1)] dp1 [[0]*(C+1) for i in range(R+1)] [0]*(C+1) for i in range(R+1) for i in range(R+1) i range(R+1) range R+1 R 1 for i in range(R+1) [0]*(C+1) [0] 0 C+1 C 1 dp2=[[0]*(C+1) for i in range(R+1)] dp2 [[0]*(C+1) for i in range(R+1)] [0]*(C+1) for i in range(R+1) for i in range(R+1) i range(R+1) range R+1 R 1 for i in range(R+1) [0]*(C+1) [0] 0 C+1 C 1 dp3=[[0]*(C+1) for i in range(R+1)] dp3 [[0]*(C+1) for i in range(R+1)] for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	 i range(1,R+1) range 1 R+1 R 1 for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	 j range(1,C+1) range 1 C+1 C 1 for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	 x y ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)) (dp0,0) dp0 0 (dp1,dp0) dp1 dp0 (dp2,dp1) dp2 dp1 (dp3,dp2) dp3 dp2 t=lis[i-1][j-1] t lis[i-1][j-1] [i-1] lis i-1 i 1 j-1 j 1 x[i][j]=max(x[i-1][j],x[i][j]) x[i][j] [i] x i j max(x[i-1][j],x[i][j]) max x[i-1][j] [i-1] x i-1 i 1 j x[i][j] [i] x i j x[i][j]=max(x[i][j-1],x[i][j]) x[i][j] [i] x i j max(x[i][j-1],x[i][j]) max x[i][j-1] [i] x i j-1 j 1 x[i][j] [i] x i j if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	 t!=0 t 0 dp1[i][j]=max(dp1[i][j],x[i-1][j]+t) dp1[i][j] [i] dp1 i j max(dp1[i][j],x[i-1][j]+t) max dp1[i][j] [i] dp1 i j x[i-1][j]+t x[i-1][j] [i-1] x i-1 i 1 j t if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	 y!=0 y 0 x[i][j]=max(x[i][j],y[i][j-1]+t) x[i][j] [i] x i j max(x[i][j],y[i][j-1]+t) max x[i][j] [i] x i j y[i][j-1]+t y[i][j-1] [i] y i j-1 j 1 t print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1])) print max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1]) max dp0[-1][-1] [-1] dp0 -1 -1 dp1[-1][-1] [-1] dp1 -1 -1 dp2[-1][-1] [-1] dp2 -1 -1 dp3[-1][-1] [-1] dp3 -1 -1 if __name__ == '__main__':
	main() __name__ == '__main__' __name__ '__main__' main() main def main():
	R,C,K=map(int,input().split())
	lis=[[0]*(C) for i in range(R)]
	for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	dp0=[[0]*(C+1) for i in range(R+1)]
	dp1=[[0]*(C+1) for i in range(R+1)]
	dp2=[[0]*(C+1) for i in range(R+1)]
	dp3=[[0]*(C+1) for i in range(R+1)]
	for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1])) def main():
	R,C,K=map(int,input().split())
	lis=[[0]*(C) for i in range(R)]
	for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	dp0=[[0]*(C+1) for i in range(R+1)]
	dp1=[[0]*(C+1) for i in range(R+1)]
	dp2=[[0]*(C+1) for i in range(R+1)]
	dp3=[[0]*(C+1) for i in range(R+1)]
	for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1])) main input=sys.stdin.readline sys.stdin.readline input
import sys
input=sys.stdin.readline
def main():
	R,C,K=map(int,input().split())
	lis=[[0]*(C) for i in range(R)]
	for i in range(K):
		a,b,c=map(int,input().split())
		lis[a-1][b-1]=c
	dp0=[[0]*(C+1) for i in range(R+1)]
	dp1=[[0]*(C+1) for i in range(R+1)]
	dp2=[[0]*(C+1) for i in range(R+1)]
	dp3=[[0]*(C+1) for i in range(R+1)]
	for i in range(1,R+1):
		for j in range(1,C+1):
			for x,y in ((dp0,0),(dp1,dp0),(dp2,dp1),(dp3,dp2)):
				t=lis[i-1][j-1]
				x[i][j]=max(x[i-1][j],x[i][j])
				x[i][j]=max(x[i][j-1],x[i][j])
				if t!=0:
					dp1[i][j]=max(dp1[i][j],x[i-1][j]+t)
					if y!=0:
						x[i][j]=max(x[i][j],y[i][j-1]+t)
	print(max(dp0[-1][-1],dp1[-1][-1],dp2[-1][-1],dp3[-1][-1]))
if __name__ == '__main__':
	main()